Means for acoustical correction



F. J. SERSEN ET AL.

'MEANS FOR AOOUSTIGAL CORRECTION Filed July '18, 1929 W AV/lIllIlllll/llll//ll INVENTOR5 fJSERsE/v mw K. B. CONGERJR Y mi? ATroRNYs ,mmmmmrmmmmmmmmmmmmmmmm.

Nov. 17, 1931.

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yPatented Nov; 17, 1931 Y J'. SERSEN, 0F BROOKLYN,` vAND KENYON B. CONGER, JR., or ARDSLEY oN HUDSON, NEW YORK e f MEANS ron Acousrrcancormncrron v Application ledl'uly 18,

This invention relates to means for ,acousf tical correction. j Y

`It is among the prime objects ofthe present invention to provide a noveland imt proved sound-deadeningmember which will absorb soundl waves and prevent improper reflection thereof.A v

` A further obj ect of the present invention is to provide a sound-deadeningmember having f maximum sound-deadening surface within minimum'dimensions. ,y 1

A further object of the presentfinvention is to provide a device of the charactendescribed, which includes associatedv portions 1'5 having variouslyA characterized sound wave deadening properties, whereby the device will operate to deaden sound wavesof widely varied frequency. Y y

A further object of the present invention T20 is to provide a device of the character de;

`scribed including a backingmember kand extending lowrfrequency deadenlng members with which high frequency deadening members are associated, whereby the whole forms a novel, improved and compact structure designed` to deaden sound waves of varying frequencies. v e l Other objects of the present invention 1nclude the combination and vinterrelation.of parts whereby the whole forms a novel, sim-v ple and improved construction read1ly designed to meet the demands of economlc manufacture. v; .1

Further objects and advantages ofthe present invention will be apparentefrom fa consideration of thevfollowing specification taken ,in conjunction with the accompanying drawings, in which 4o the present invention, and Y Fig. 2 is aside elevation broken away, as

indicated'by the lines 2 2 in Fig. 1.

f Referring'fmore particularly to the draw- Figure 1 is a top plan view kof one form ofv 1929. Seria1'No.'379,273. l f may b'e secured to the edges 11r of the body. In theenibodiment of the invention hereln shown the body and edges thereof are formed integrally of suitable sound-deadening material,itv being' preferable to employsmaterial having a low natural period of vibration,

such as the various libre boards now on` the market or any other'equivalent cellular ma-V terial. Itis understood that the present in-V vention is not confinedto the specific range of frequencies tof which thebody is formed norto the material of the body. It willbe understood that if desired the body and sidey ing without any effective free period of vibration. In such a case, it will be understood'that the ribs or bridges, as will be hereinafter vvdescribed, will have characterictic frequency resonance to ,accomplish the desired ends. The grille 12 may be of anydesired artistic design kandinaybe formed of any desired material, Y it being understood Vvthat the grille-will not in usual constructions ofthe device,have an active part inthe sound deadening. l n -V p y e Associated with thebacking of the body e and extending outwardly therefrom topa'n extent preferably less than the sides l1, a plurality of ribs or bridges 13 are provided. In the preferredfform of the invention here illustrated, the bridges 13 vareformed integrally with 4the body, lit being understood that the body and bridges are `formed of a low frequency resonant material.y If desired, however, the bridges may be formed walls thereof maybe a simple metallic casseparately and associated with the body, in

which case the body may be formed of metal or other non-resonant material as herein after described. 1T he arrangement rof the bridges 13l is such that they providea plurality of spaced troughs y14 therebetween.

Associated' within the body and with the ribs 13, a high frequency responsive deadeningmaterial, such as felt or ythe like,-is provided as indicated by the numeral 15. The high frequency? absorbing materialyis laid within the troughs 14 formed by the ribs 13 and extends over the ribs and into the next adjoining trough in such a manner that ya Vcontinuous piece. ofthe felt may be used extending entirely across the device.

The material 15 may be secured within the device in any suitable manner such as by gluing, or if desired by other equivalent securing means.

In the operation of the device, it will be understood that the device may be secured to a wall, ceiling or the like, by suitable securing means which may extend throuoh apertures 16 in corners of the device. The grille 12 is designed to permit the free entrance of sound waves to the inside of the body, and, at the same time, provides an artistic covering for the body. As sound waves enter the body, the high frequency material, such as felt, indicated by the numeral 15, will absorb and deaden the high frequency sound waves and will prevent their reflection from the device. The low frequency waves would normally be reflected from the single high frequency felt, but in the present instance due to the support of the felt by the low frequency ribs 13 of the body 10, the body and/or ribs will operate with the felt to absorb and deaden the low frequency waves. Thus in the simple structure herein presented, both high and low frequency waves will be absorbed and deadened by the device. It will be understood that intermediate or parasitic WavesV will also be largely absorbed due to the fact that iio sharp line of division between the absorption powers of the low and high frequency ma terials will be found.

The present invention not only provides a structure einbod ing co-operatively acting low andhigh frequencyv deadening inaterials, but by the construction of the device, a maximum sound-absorbing surface is provided within minimum dimensions of the device. It will be seen that by the ribs 13 and troughs formed thereby, thev felt is laid in wave formation over the ribs to provide crests and hollows which materially increases the sound-deadening surface provided.

From the foregoing it will readily be seen that the present invention provides a novel, simple and improved construction which will be efficient in operation and Well designed to meet the demands of economic manufacture.

It will be understood that the invention is not confined to the specific structure or materials herein recited, but that numerous changes and modilications and the fnll'use of equivalents may be resorted to without departing from the'spirit or scope of the invention as outlined in the appended claims.

Vliat is claimed is:

1. A device of the character described, including a body, low frequency sounddeadening members on said body, and'high frequency sound-deadening material applied to and conforming to the shape of the body and said members.

2. A device of the character described, in-

cluding a body, low frequency sound-deadeiiing members in said body, and high frequency sound-deadening material associated therewith, said lon7 frequency members including extending ribs carried by the back of said body, said high frequency material being laid over said ribs to provide a crestand-hollow receiving surface.

8. In a device of the character described,

Vthe combination with a body, of a plurality of outstanding ribs on the body having low free periods of vibration whereby said ribs will act to absorb and prevent reflection of low yfrequency sound waves, and means applied to and conforming to the shape of said ribs and the body for preventing reflection of high frequency sound Waves.

4. ln a device of the character described, the combination with a body, of a plurality of outstandingV ribs having low free periods of vibration whereby said ribs will act to absorb and prevent reflection of lou7 frequency sound waves, and means associated with said ribs for preventing reflection of high frequency sound waves said means coinprising a high frequency absorbing felt associated with said ribs.

5. Iii a device of the character described, the combination with a body, of a plurality of outstanding ribs having low free periods of vibration whereby said ribs will act to absorb and prevent reflection of loW frequency sound Waves, and means associated with said ribs for preventing reflection of high frequency sound Waves, said means comprising a high frequency absorbing felt associated with said ribs and laid thereover to provide a corrugated sound-receiving surface.

6. In a device of the character described, a low frequency resonant body having extending ribs formed integral therewith, and

material applied to and also conforming to the shape of said body and ribs for absorbing relatively high eiciency sound waves.

7. In a device of the character described, a low frequency resonant body having extending ribs formed integral therewith, and high frequency responsive felt carried by said ribs.

8. Ina device of the character described, a low frequency resonant body having extendinfr ribs formed integral therewith, and high frequency responsive felt carried by said ribs, said felt being associated with said ribsand with the back of'said body to provide a corrugated sound receiving surface.

9. In a device of the character described, a low frequency resonant body having extending ribs formed integral therewith, and high frequency responsive felt carried by said ribs, said feltbeing yassociated with said ribs and with the back of said body to provide a corrugated sound receiving surface,

andan ornamental grille carried by .said 1.30

body, said grille permitting the passage of sound waves therethrough.

10. A device of the character described,

including a frame having a rear wall, fory Wardly extending side walls, and integral parallel ribs Within said Walls, felt sounddeadening material within said body extending over said ribs to provide a felt corrugated sound-deadening surface, and an apertured cover plate for vsaid body secured to said side Walls in spaced relation to the ends of said corrugations.

FRED J. SERSEN.

y KENYON B. coNGEmJB. 

